1. Field of the Invention
The present invention relates to novel anisomycin derivatives, to pharmaceutical compositions containing an effective amount of the same to treat cancer or to treat and/or prevent infections by fungi and/or protozoa, and to methods of treating cancer, treating and/or preventing infection by fungi and/or protozoa, and killing fungi and/or protozoa.
2. Discussion of the Background
Anisomycin is an antibiotic having the structure shown in formula (I) below. Anisomycin is produced by actinomycetes, and it is known to have strong cytotoxic activity due to its inhibitory effect on protein synthesis (J. Biol. Chem., vol. 242, p. 3226, 1967). ##STR2##
The application of anisomycin or derivatives thereof as anticancer agents, antifungal agents, antiprotozoan agents and the like has been attempted. For example, there is a description in Japanese Patent Application Laid-Open No. 62-89659 regarding the anticancer effect of a 3- or 4-acyloxy substituted anisomycin. However these derivatives have a low effect in vivo compared with their strong cytotoxic activity in vitro. Thus, they are not practical for use as medicines, and the need for anisomycin derivatives which exhibit strong in vivo anticancer, antifungal and antiprotozoan activities is still felt.